Orange County Sheriff’s officials said Tuesday that they were “extremely troubled” that it took at least 16 hours for deputies to realize three inmates had escaped last week, as new details emerged about the lengths the trio went to break out of the high-security lockup in Santa Ana.

With the inmates now at large for five days, the jail has come under intense scrutiny for several policies that some believe may have made the escape easier.

Jail personnel conduct only two physical head counts of inmates per day, one at 5 a.m., the other at 8 p.m. Investigators believe the three men vanished after the 5 a.m. check, and the escape was not discovered until late Friday night.

Lt. Jeff Hallock, a department spokesman, said at a news conference Tuesday that “immediate steps have been taken” to improve the inspection process but would not provide any specifics.

Court documents made public Tuesday offered the most detailed description of the escape scheme yet, suggesting that more than 17 hours may have elapsed before evidence of the jail break was discovered.

Jail staff first realized something was wrong around 8 p.m. Friday during a nightly count of inmates that came up three short, according to the arrest warrants filed late Monday. The warrants make no mention of a jailhouse brawl that sheriff's officials have said delayed completion of the bed check until about 9 p.m.

After identifying the missing men as Jonathan Tieu, Bac Duong and Hossein Nayeri, deputies checked the inmates’ schedules to make sure they hadn't been in court that day or been left behind in a visitor area. They also checked whether the inmates were in classes offered at the jail.

With no leads, deputies performed a second head count, confirming what many of them probably were dreading — the three men weren’t merely missing, they might have escaped.

At 8:45 p.m., deputies launched a physical search of the entire facility. Seven inmates claimed they saw Tieu, Duong and Nayeri during the jail’s 5 a.m. head count but did not see them the rest of the day.

As teams swept every cell, bunk bed and dorm, other deputies scoured the building's roof and plumbing tunnels, finding makeshift ropes, cut-apart gates and sawed-open vents. Slowly, investigators were able to trace the trio’s path from Module F, the fourth-floor dormitory where they were housed, to a rope of knotted bed sheets they used to descend from the roof.

Sheriff's Department officials have said the escape probably began with the inmates cutting through a metal screen in their fourth-floor cell. This gave them access to a plumbing tunnel, but according to the warrant, deputies discovered that the tunnel would quickly lead the escapees to a ventilation shaft.

A deputy who had been searching the plumbing tunnel said he found the shaft's security bars had been cut away. About two feet below the shaft's entrance was a white bed sheet tied into a sling, with another sheet tied to more security bars, according to the affidavit.

“This was used as a way for the inmates to pull themselves up into the vent,” one deputy wrote.

Once inside the shaft, the escapees had to remove multiple “ventilation louvers,” or shutters, before they reached a trap door leading to the outer edge of the roof, according to the reports.

That area is outside a security gate that keeps inmates in a recreation area. Hallock said the fact that inmates typically use the roof for recreation purposes is “one of many design flaws” of the nearly 50-year-old jail.

The reports in the warrants say the escapees “sawed” through some of the security bars but make no mention of any tools they may have used or from where they may have gotten them.

Once atop the jail, the inmates cut barbed wire from the rooftop's edge and used the bed sheets to rappel to the ground, deputies wrote.

About 10:30 p.m., investigators found two pairs of jail-issued sandals and a paper bag containing more rope that the trio presumably left on the roof before making their way to freedom.

Since the escape, the Sheriff’s Department has conducted a “roof-to-basement” check of the entire jail, Hallock said.

“The preliminary investigation into the escape has caused the sheriff concern as to some of the jail inmate count practices and how they were conducted,” he added. “The sheriff is extremely troubled by the time it took the staff to determine the three inmates housed in a maximum security jail were unaccounted for.”

The Orange County Grand Jury has called on the Sheriff’s Department to improve antiquated surveillance systems in county jails six separate times, from 2008 to 2014. An $11-million plan to revamp those outdated camera setups was not launched until last year.

It remains unclear whether Module F is equipped with cameras. In a report published in 2014, an Orange County Grand Jury said surveillance equipment in the county’s adult and juvenile facilities were extremely outdated, with some deputies left to review videotapes.

“After touring all jail facilities, the grand jury surveyed the video systems at each jail, which range from severely outdated VHS tape technology, to touch screen operations. Each jail has a different system,” the report read. “This grand jury again found that all jails were lacking adequate video monitoring equipment to protect both the inmates and the staff. Recommendations by the previous six grand jury reports have not changed this fact.”

While Men’s Central Jail was not among those equipped with a VHS system, the facility’s camera setup did allow for several blind spots, according to a member of the grand jury who requested anonymity because grand jury members are not allowed to speak publicly about their findings. The grand jury member wondered aloud if increased surveillance could have done anything to prevent the escape.

“This has been a problem that has been building for some years and now, boom, here we are,” the grand jury member said. “Had the responses been taken seriously and the funds allocated in the past, we wouldn’t be here.”

The Sheriff’s Department launched a project to upgrade its camera system at all county jail facilities last year, with an approved budget of nearly $11 million, the reports show. Between 1,500 and 2,000 cameras are to be installed as part of the plan.

Hallock said the upgrade process was ongoing at all jails but declined to elaborate.

Questions about the surveillance systems were among several raised Tuesday, as local leaders continued to try to understand how the three men managed to get through several layers of metal, steel and rebar undetected.

“We were all scratching our heads,” said County Supervisor Todd Spitzer, who announced a $200,000 reward Tuesday for information leading to the capture of the fugitives. “How on Earth did this happen?”

Spitzer said he was particularly concerned about delays of Nayeri’s trial date.

The 37-year-old was arrested in 2013 and charged as part of a plot to kidnap and torture a wealthy marijuana dispensary owner in hopes of forcing him to surrender $1 million. Nayeri and his accomplices allegedly burned the man with a blowtorch and severed his penis, then left him to die in the Mojave Desert, court records show.

Hallock would not say whether the men’s pending trial dates helped motivate the escape, but all three were due in court to answer charges that could carry life sentences within the next two months. Nayeri was scheduled to face a pretrial hearing Feb. 2, 10 days after the escape. Duong was slated for a pretrial hearing on an attempted murder charge Feb. 8, and Tieu was to be retried in a 2011 gangland murder the following month.

During the news briefing, Hallock defended the sheriff’s policy of holding inmates awaiting trial for violent crimes in the dormitory-style housing. Corrections experts have said the three men should have been detained in individual holding cells.

Hallock, however, said at least half the men held in Module F are violent offenders.

“Each of the three inmates were housed appropriately in a maximum security jail,” he said.